If you're a fan of Cleveland, your team has about 1 chance in 100 of not making the postseason.
If you're a Twins fan, your team has slightly better than a 1 in 5 chance of making it.
So there's really more than five games of separation between the teams as they begin a three-game series at Target Field.
The playoff projections on MLB.com come from the fabulously geeky Fangraphs.com web site, which is one I tend to avoid for good reason: if I dive in when I should be doing something else, it is very, very difficult to get back on task. (OK, back to this post. I just got sidetracked by an article about baseball's drug testing program called "Better playing through chemistry ... Still.")
Stay ... on ... task.
So how are those playoff projection chances computed? Here's the boilerplate explanation from MLB.com: "Postseason projections are courtesy of FanGraphs and indicate each team's probability of winning the division or wild card, or any postseason berth. Projections are based on thousands of Monte Carlo simulations of the remaining seasons' schedule. They incorporate up to date player projections, current roster composition, playing time projections and the remaining schedule."
If you want to go down another rabbit hole, you can read up on Monte Carlo simulations here. The too-short definition is that a Monte Carlo simulation takes into account as many variables as possible in a situation that can't be easily predicted.
The easiest way to explain why the Twins have only a 22.2 percent chance of being in the postseason -- even though they are only a half-game behind right now -- is the number of teams currently crowded around the second Wild Card spot in the American League. There are four teams within two games of the spot, with the Angels currently in the lead, and four more within 3 1/2 games.